Composite weld rod



0d- 17 1950 L.. M. BARBE-BOUJouRs 2,525,352

Nw EJ /w w E m u m m m W w /J COMPOSITE WELDROD med April 15. 194sPatented Oct. 17, 1,950

COMPOSITE WELD ROD Ludovico Morlon Barbe-Bonjours,

Vigo-Espineiro, Spain Application April 15, 1948, Serial No; 21,206 InSpain April 22,1947 y This invention relates to a new and improvedcombination arc-welding electrode.

This combination electrode has a main electrode, which is the usual rodor'wire.y Said main electrode may have an axial space which is lled witha core of fusible metal or metals, in order to deposit an alloy of thematerial of the main electrode and of the core.

.This main electrode is surrounded by an auxillaryr electrode, which isa helix. The upper or outer end of this helix is conductively connectedto said main electrode. Below this conductive f 3 claims. (o1. 21a-s)connection, the helix is insulated from said main electrode. n

Other features of the invention are disclosed in the annexed descriptoinand diagrammatic drawings.

Fig. 1 is an elevation which shows the improved electrode applied tothework, and the result of the formation of the arc. Y

Fig. 2 is an elevation of the combination electrode. j j

Fig. 3 isa plan view of Fig. 2. v y

The main electrode is a rod I, which is made of steel. In thisembodiment, the main rod electrode I has an axial passage', which has acore of alloying material, such as copper or ferrosilicon.

The arc is formedv atthe lower end of the combination electrode. Saidcombination electrode includes a helical strip 4, which is made ofcopper, aluminum or other suitable material.

A sleeve 3 is xed to the outer longitudinal face of rod I. This sleeve 3is made of material which is insulating and which is fused in the arczone.

Said sleeve 3 is a composition of silica and bases,

end of rod I. The rod I extends above the top of` sleeve 3. The strip 4'is fixed conductively to rod I, above the top of sleeve' 3.

Below the conductive connection of strip 4 to rod I, said strip 4 isenclosed by a surface sleeve 5, which is made of a silica-calciumfluoride composition. 'f

When the arc is struck between the tip of this combination electrode andthe work-piece 8, said arc is struck initially between the rod I and itscore, because the bottom end of rstrip 4 is protected by the sleeves 3and 5.

As shown in Fig. 1, the heat of thearc forms a space 6` within the outersleeve 5, in which the molten metal of rod I and its core fall in theform of drops on the work-piece 8, thus protecting said molten metalfrom oxidation. As also shown in Fig. l, the heat of the arc fuses thelower part of sleeve 3, thus exposing the bottom end of strip 4. The-molten material of sleeve 3 produces a protective outer layer 1, whichalso protects the fused metal in space 8 from oxidation. Due to its morerefractory composition, the lower end of outer sleeve 5 remains unfusedfor a time, while the rod I and its core and the sleeve 3 are fused inthe arc zone.

As soon as the lower part of sleeve 3 is'fused, the welding currentflows in parallel through rod I and strip 4, so that the arc is struckthrough strip 4. This action will be delayed, because rod I and its coreare more easily fused than sleeve 3.

The core has the lowest fusing temperature.

When the welding current flows through strip 4, such current generatessubstantial heat, which aids in fusing the material ofr rod I and itscore.

If the height of the protective space 6 becomes too great, thusresultingA in the breaking of the aro between the work-piece 8 and. rodI and its core, the arc ismaintained by strip 4, thus providing enoughheatv to cause drops of molten metal toy fall from rodk I and its core.If the strip 4 is made of aluminum, it acts as a deoxidizing agent, andthe oxidation ofthe aluminum provides additlonalvheat in the arc zone.

With an electrode of the type indicated and in service, a voltaic arcwith Joule effects will be developed during the welding operation. Thisis brought about by the fact that inasmuch as the core I and spiral 4are insulated from each other by liner 3, the current supply to the arcis of parallel type with these paths both leading to the arc zone, butinsulated above such zone. As a result, a particular type of weldingaction will develop. This will be understoody from the following: l

Both the core vI and the metallic strip 4 are connected with the currentsupply and both reachv 'to the arcing zone, but the two are insulatedfrom eachother by the liner 3, except in the arcing zone. Hence,v duringwelding activity, current ,will flow in both paths with the iiowthroughthe core causing fusion ofthe latter within the arc ing duringthe operation, since fusing of the core inherently increases the lengthof the arc.

When this distance becomes sufficiently great as to affect the dischargeof current, current ow through the core ceases, and the entire currentsupply passes to strip il, causing the latter to become highly heated, acondition which acts to begin fusing action on the covering and theliner in the end zone of the electrode. With the fusion of covering andliner the electrode lowers, thus decreasing the distance between coreand welding point and again establishing a circuit path through the coreand restoring the welding arc conditions.

Strip 4 thus serves as a control for regulating the length of thewelding arc. When forced to form the sole current path, it becomes theagency for fusing the liner and covering to the extent needed to restorethe normal arc conditions, and during the fusing action a correspondinglength of the strip is fused, thus enabling the electrode to lower torestore the arc conditions. Hence, the electrode advance is more or lessby stage development and is produced through the effects set up by thecycle which rst breaks the core path to affect the arc, then fuses thecovering and liner through strip action activity tc lower the electrodeand again complete the arc, the sequence being developed each time thearc is affected, the latter timing the development start, the sequenceproceeding through the cycle in regular development, thus creating thev-oltaic arc conditions with Joule effects.

A number of advantages accrue by the use of the invention. For instance,the metallic spiral 4 regulates, by Joule effects, the length of thearc, permitting the melting of the core to take place within a coveringcone, the latter being provided by the covering 5 and the inner lining3, these sealing the working arc from the atmosphere so that the fusionor melting action during welding are produced under the perfectconditions of insulation from any atmospheric gases. Hence, theconditions of furnace melting are being set up. In addition, it avoidsthe need of large quantities of clinker or slag to produce suchinsulation, the technique usually employed, with lconsequent need formanually knocking the welding and subjecting the material to alternateheating and cooling with consequent damage.

Since strip 4 is insulated from the core and peripherally surrounds thelatter, the strip becomes active, especially when forming the solecurrent path, in developing an induced current in the core which tendsto oppose the constitution of the arc, tending to delay the later,thereby making possible the heating of edges of the work piece andproducing a homogeneous dissolution characteristic between thecontributing and base metals which are providing the weld, as well asassuring the fusing of the covering and liner in the end zone of theelectrode.

I claim:

1. A combination arc-welding electrode, said combination electrodecomprising a metallic electrode rod which is fusible at arc temperature,said rod having a longitudinal axis and an arcforming tip, alongitudinal sleeve of heat-insulating and electrical-insulatingmaterial which is fusible at arc temperature, said sleeve being fixed tothe outer longitudinal face of said rod and extending substantially tosaid arc-forming tip, a metallic helix which has spaced turns, one endof said metallic helix extending substantially to said arc-forming tip,said helix being fusible at arc temperature, said helix beinglongitudinal and being mounted on the outer longitudinal face of saidsleeve, the other end of said helix being conductively fixed to said rodrearwardly of said arc-forming tip, another longitudinal sleeve made ofheat insulating and electrical-insulating material which is fusible atarc temperature, said last-mentioned sleeve being mounted longitudinallyon the outer face of said helix and extending substantially to saidarc-forming tip, said first-mentioned sleeve having a higher meltingpoint than said rod and said helix, said secondmentioned sleeve having amelting point which is sufficiently higher than the melting point ofsaid first-mentioned sleeve to maintain said second-mentioned sleevetemporarily unfused at said arc-forming tip when said rod and saidfirstmentioned sleeve and said helix are fused at said arc-forming tip,said second-mentioned sleeve prov'ding an enclosure which extendsforwardly in the arc zone of said rod and said helix and saidfirst-mentioned sleeve during the operation of the arc.

2. A combination arc-welding electrode, said combination electrodecomprising a metallic electrode rod which is fusible at arc temperature,said rod having a longitudinal axis and an arcforming tip, alongitudinal sleeve of heat-insulating and electrical-insulatingmaterial which is fusible at arc temperature, said sleeve being fixed tothe outer longitudinal face of said rod and extending substantially tosaid arc-forming tip, a metallic helix which has spaced turns, one endof said metallic helix extending substantially to said arc-forming tip,said helix being fusible at arc temperature, said helix beinglongitudinal and being mounted on the outer longitudinal face of saidsleeve, the other end of said helix being conductively xed to said rodrearwardly of said arc-forming tip, anotherlongitudinal sleeve made ofheat insulating and electrical-insulating material which is fusible atarc temperature, said last-mentioned sleeve being mounted longitudinallyon the outer face of sad helix and extending substantially to saidarc-forming tip, said first-mentioned sleeve having a higher meltingpoint than said rod and said helix, said secondmentioned sleeve having amelting point which is sufficiently higher than the melting point ofsaid first-mentioned sleeve to maintain said second-mentioned sleevetemporarily unfused at said arc-forming tip when sad rod and saidfirstmentioned sleeve and said helix are fused at said aro-forming tip,said second-mentioned sleeve providing an enclosure which extendsforwardly in thearc zone of said rod and said helx and saidfirst-mentioned sleeve during the operation of the arc, said electroderod being oxidizable in the fused state, said helix being made 0f metalwhich is a deoxidizing agent in the fused state.

3. A combination arc-welding electrode, said combination electrodecomprising a metallic electrode rod which is fusible at arc temperature,said rod having a longitudnal axis and an arcforming tip, a longitudinalsleeve of heat-insulating and electrical-insulating material which islfusible at arc temperature, said sleeve being fixed to the outerlongitudinal face of said rod and extending substantially to saidarc-forming tip, a metallic helix which has spaced turns, one end ofsaid metallic helix extending substantially to said arc-forming tip,said helix being fusible at arc temperature, said helix beinglongitudinal and being mounted on the outer longitudinal face of saidsleeve, the other end of said helix being conductively fixed to said rodrearwardly of said arc-forming tip, another longitudinal sleeve made sof heat insulating and electrical-insulating material which is fusibleat aro temperature, said last-mentioned sleeve being mountedlongitudinally on the outer face of said helix and extendingsubstantially to said arc-forming tip, said first-mentioned sleevehaving a higher melting point than said rod and said helix, saidsecondmentioned sleeve having a melting point which is sufciently higherthan the melting point of said rst-mentioned sleeve to maintain saidsecondmentioned sleeve temporarily unfused at said arc-forming tip whensaid rod and said rstmentioned sleeve and said helix are fused at saidarc-forming tip, said second-mentioned sleeve providing an enclosurewhich extends forwardly in the arc zone of said rod and said helix andsaid first-mentioned sleeve during the operation of the arc, said helixhaving a lower melting point than said rod.

LUDOVICO MOR/LON BARBE-BOUJOURS.

6 REFERENCES CITED The following references are of record in the nle ofthis patent:

UNITED STATES PATENTS Number Name Date 1,356,468 Peters et al Oct. 19,1920 1,709,474 Hawley Apr. 16, 1929 1,657,521 Stresau et a1 May 10, 19321,944,753 Mathias Jan. 23, 1934 2,001,848 Nyquist May 21, 1935 2,054,609Strohmenger Sept. 15, 1936 2,067,630 Franks Jan. 12, 1937 2,083,309Applegate June 8, 1937 2,345,758 Lincoln et al. Apr. 4, 1944

